Oil-circuit interrupter



Dec. 31, 1929. CLAALBQRG I 1,741,966

OIL CIRCUIT INTERRUPTER Filed Jan. 29, 1927 I ."H!! H WITNESSES I INVENTOR Christian flalborg w 3. Y Y

PITTORNEY Patented Dec. 31, 1929 UNETED STATES PATENT orricn CHRISTIAN AALBORG, OF PITTSBURGH, PENNSYLVANIA, ASSIGNOR TO WESTINGHOUSE ELECTRIC & MANFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA.

OIL-CIRCUIT INTERRUIPTER Application filed January 29, 1927.

One object or my invention is to provide a fluichfllled circuit interrupter that shall partially replenish the supply of insulating fluid with each operation.

rinother object of my invention is to provice a fluidinsulated circuit interrupter that shall eject the contaminated insulating fluid at each operation and automatically replace the ejected insulating fluid.

In the operation of fluid-insulated cicuit interrupter-s, a certain amount of the insulating fluid is broken down by the action of the electrical arcs Whenever the circuit interrupter is operated. The breaking dOX *n of the oil isaccompanied by the formation of sludges and the liberation of suspended particles of carbon in the insulating fluid. The impuri es just mentioned impair the dielectric strength of the insulating fluid and, it permitted to accumulate, may result in flashovers and break-downs.

I propose to cause the forces of the arcs which are drawn Where such circuit interrupters are opened to eject the contaminated oil in the vicinity of the contact members at each such operation and to replace the ejected insulating fluid by a fresh supply.

T he single figure of the accompanying drawing is a view, partially in elevation and partially in section, of a circuit interrupter embodying my invention.

ll ly invention comprises, in general, a circuit interrupter 1 comprising the usual tank 2, cover 3, stationary contact members 4 and a bridging member 5 that are suspended in a body of insulating fluid 6, such as oil, and conduits 7 that are disposed adjacent to the stationary contact members 4 for permitting a certain amount of the insulating fluid 6 to escape therefrom at each operation of the circuit interrupter.

The stationary contact members i and the bridging member 5 may be of any preferred type. Each of the conduits 7 comprises a portion 8 of bellshape that extends over and partially encloses each of the stationary contact members a and a pipe 9 or insulting ma- Serial No. 164,528.

terial that extends upwardly through the cover 3 of the circuit interrupter 1 and discharges into a drain pipe 11.

A reservoir 12 is disposed adjacent to the circuit interrupter 1 and is connected by a pipe 13 to the cover 3. The reservoir 12 is filled with insulating fluid 6 and is preferably so disposed that the fluid level therein is above the cover 3 of the circuit interrupter 1 and below the drain pipe 11. A check valve ll is placed between the insulating fluid 6 and the reservoir 12 to prevent pressure Waves being transmitted into the reservoir 12, and check valves 15 are placed in the conduits 7 to prevent the ejected oil from draining back to the tank 2.

Upon the operation of the circuit interrupter 1 to open an electric circuit, an arc is drawn between the bridging member 5 and stationary contact members l. The are acts with suflicient violence to generate a considerable amount of gas and burn a quantity of the insulating oil 6 that is trapped in the bell-shaped portion 8 and ejected through the pipe 9 to the drain pipe 11. Since the most violent agitation and contamination of the insulating fluid 6 occurs Within the portion 8, the insulating fluid 6, of poorest quality, is forced out of the circuit interrupter through the conduits 7 during the agitation in the insulating fluid. A sufficient amount of the insulating fluid 6 flows from the tank 12 through the pipe 13 into the circuit interrupter to replace the insulating fluid 6 that has been ejected.

Accordingly, I have provided a circuit interrupter in Which the insulating fluid that has been contaminated is ejected. by the explosive force of the active, or subsequently drawing, are and the ejected insulating fluid is automatically replaced.

It is to be understood that such changes may be made in the a rangement, disposition and number of component parts of my invention as may fall Within the scope of the appended claims.

I claim as my invention:

1. In electrical apparatus, the combination With an enclosed tank, an electrical device mounted therein, insulating fluid surrounding the electrical device and a reservoir for the insulating fluid, of a chamber disposed about the electrical device, and a discharge conduit for the fluid connecting the said chamber to the exterior of the tank whereby, upon the occurrence of a disturbance in the electrical device to contaminate the insulating fluid, the contaminated insulating fluid is discharged through the conduit and is replaced by fluid from the reservoir.

2. In a circuit interrupter, the combination with an enclosed tank, a pair of relatively movable contact members mounted therein, insulating fluid surrounding the contact members and a source of supply for the in sulating fluid, of a fluid discharge conduit terminating in a trap that is connected to the contact members whereby, upon the occur rence of an are between the contact members, the insulating fluid within the trap is ejected through the conduit and is replaced by fluid from the source of supply.

3. In a circuit interrupter, the combination with i an enclosed tank, a plurality of contact members mounted therein, insulating fluid surrounding the contact members and a source of supply for the in sulating fluid, of an inverted dome shaped chamber disposed on each contact member, and a discharge conduit for the fluid contain ing a valve member connecting the said chamber to the exterior of the tank whereby, upon the occurrence of an are between the groups of contact members, the insulating fluid adjacent to each arc is ejected from the tank and is replaced by fluid from the source of supply.

4. The combination, in a circuit interrupter comprising a main tank containing an arc extinguishing liquid and contact members, of an auxiliary tank for automatically supplying liquid to the main tank, and means cooperating with each contact member for segregating the liquid contaminated by the arc at the contact members and to discharge the said contaminated liquid from within the main tank.

5. The combination, in a circuit interrupter comprising a main tank containing an arc-extinguishing liquid and contact members, of an auxiliary tank for automatically supplying liquid to the main tank, and means comprising a dome shaped member and a discharge pipe so associated with each of the contact members that the liquid about the contact members will be automatically discharged from within the main tank by the pressure developed upon the opening of the circuit interrupter.

6. A contact member of an oil-immersed circuit interrupter characterized by an inverted dome shaped member supported on its end adjacent to its contact surface, a discharge conduit connected to the dome and a valve within the said conduit in the vicinity of the dome.

7. In a circuitdnterrupter tank containing a liquid, the combination with a contact member, of a trap attached thereto adjacent its contact surface, and a discharge conduit for the liquid connecting the trap with the exterior of the tank.

8. In a circuit-interrupter tank containing a liquid, the combination with a contact member, of a trap attached thereto adjacent its contact surface, a drain exterior of the tank, and a discharge conduit connecting the trap with the said drain.

5). In a circuit-interrupter tank containing a liquid, the combination with a contact member, of a trap attached thereto adjacent its contact surface, liquid-collecting means exterior of the tank, a discharge conduit connecting the trap with the said collecting means and a valve in the said conduit to pre vent the liquid therein from returning to the said trap.

In testimony whereof, I have hereunto subscribed my name this 28th day of January,

CHRISTIAN AALBORG. 

